OK, let's work through this together. We're starting with 798 and we're going to multiply it by 110, which means we add 798 to itself 110 times.
Step 1: 0 + 798 = 798
Step 2: 798 + 798 = 1596
Step 3: 1596 + 798 = 2394
Step 4: 2394 + 798 = 3192
Step 5: 3192 + 798 = 3990
Step 6: 3990 + 798 = 4788
Step 7: 4788 + 798 = 5586
Step 8: 5586 + 798 = 6384
Step 9: 6384 + 798 = 7182
Step 10: 7182 + 798 = 7980
Step 11: 7980 + 798 = 8778
Step 12: 8778 + 798 = 9576
Step 13: 9576 + 798 = 10374
Step 14: 10374 + 798 = 11172
Step 15: 11172 + 798 = 11970
Step 16: 11970 + 798 = 12768
Step 17: 12768 + 798 = 13566
Step 18: 13566 + 798 = 14364
Step 19: 14364 + 798 = 15162
Step 20: 15162 + 798 = 15960
Step 21: 15960 + 798 = 16758
Step 22: 16758 + 798 = 17556
Step 23: 17556 + 798 = 18354
Step 24: 18354 + 798 = 19152
Step 25: 19152 + 798 = 19950
Step 26: 19950 + 798 = 20748
Step 27: 20748 + 798 = 21546
Step 28: 21546 + 798 = 22344
Step 29: 22344 + 798 = 23142
Step 30: 23142 + 798 = 23940
Step 31: 23940 + 798 = 24738
Step 32: 24738 + 798 = 25536
Step 33: 25536 + 798 = 26334
Step 34: 26334 + 798 = 27132
Step 35: 27132 + 798 = 27930
Step 36: 27930 + 798 = 28728
Step 37: 28728 + 798 = 29526
Step 38: 29526 + 798 = 30324
Step 39: 30324 + 798 = 31122
Step 40: 31122 + 798 = 31920
Step 41: 31920 + 798 = 32718
Step 42: 32718 + 798 = 33516
Step 43: 33516 + 798 = 34314
Step 44: 34314 + 798 = 35112
Step 45: 35112 + 798 = 35910
Step 46: 35910 + 798 = 36708
Step 47: 36708 + 798 = 37506
Step 48: 37506 + 798 = 38304
Step 49: 38304 + 798 = 39102
Step 50: 39102 + 798 = 39900
Step 51: 39900 + 798 = 40698
Step 52: 40698 + 798 = 41496
Step 53: 41496 + 798 = 42294
Step 54: 42294 + 798 = 43092
Step 55: 43092 + 798 = 43890
Step 56: 43890 + 798 = 44688
Step 57: 44688 + 798 = 45486
Step 58: 45486 + 798 = 46284
Step 59: 46284 + 798 = 47082
Step 60: 47082 + 798 = 47880
Step 61: 47880 + 798 = 48678
Step 62: 48678 + 798 = 49476
Step 63: 49476 + 798 = 50274
Step 64: 50274 + 798 = 51072
Step 65: 51072 + 798 = 51870
Step 66: 51870 + 798 = 52668
Step 67: 52668 + 798 = 53466
Step 68: 53466 + 798 = 54264
Step 69: 54264 + 798 = 55062
Step 70: 55062 + 798 = 55860
Step 71: 55860 + 798 = 56658
Step 72: 56658 + 798 = 57456
Step 73: 57456 + 798 = 58254
Step 74: 58254 + 798 = 59052
Step 75: 59052 + 798 = 59850
Step 76: 59850 + 798 = 60648
Step 77: 60648 + 798 = 61446
Step 78: 61446 + 798 = 62244
Step 79: 62244 + 798 = 63042
Step 80: 63042 + 798 = 63840
Step 81: 63840 + 798 = 64638
Step 82: 64638 + 798 = 65436
Step 83: 65436 + 798 = 66234
Step 84: 66234 + 798 = 67032
Step 85: 67032 + 798 = 67830
Step 86: 67830 + 798 = 68628
Step 87: 68628 + 798 = 69426
Step 88: 69426 + 798 = 70224
Step 89: 70224 + 798 = 71022
Step 90: 71022 + 798 = 71820
Step 91: 71820 + 798 = 72618
Step 92: 72618 + 798 = 73416
Step 93: 73416 + 798 = 74214
Step 94: 74214 + 798 = 75012
Step 95: 75012 + 798 = 75810
Step 96: 75810 + 798 = 76608
Step 97: 76608 + 798 = 77406
Step 98: 77406 + 798 = 78204
Step 99: 78204 + 798 = 79002
Step 100: 79002 + 798 = 79800
Step 101: 79800 + 798 = 80598
Step 102: 80598 + 798 = 81396
Step 103: 81396 + 798 = 82194
Step 104: 82194 + 798 = 82992
Step 105: 82992 + 798 = 83790
Step 106: 83790 + 798 = 84588
Step 107: 84588 + 798 = 85386
Step 108: 85386 + 798 = 86184
Step 109: 86184 + 798 = 86982
Step 110: 86982 + 798 = 87780

So, 798*110 = 87780